I use and follow the old way to revive a old dead battery, use a 1 to 4 amp charger and charge it for 3 or 4 days at the lowest amp rating you can use Same thing on low batteries that have set for 30 or more days, nice low amperage SLOW charge
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: ACTIVATING a dead battery ?
[Re: Cab_Burge]
#2959186 08/30/2108:56 PM08/30/2108:56 PM
What kind of battery are we talking about here? A sealed maintenance free or one you can pull caps or an AGM? Makes a difference. Tread carefully when dealing with dead batts. They can be sulfated, they can be shorted and they can be full of gas. Ever seen a battery go boom? I have and it's not pretty.
Re: ACTIVATING a dead battery ?
[Re: NITROUSN]
#2959245 08/30/2110:30 PM08/30/2110:30 PM
What kind of battery are we talking about here? A sealed maintenance free or one you can pull caps or an AGM? Makes a difference. Tread carefully when dealing with dead batts. They can be sulfated, they can be shorted and they can be full of gas. Ever seen a battery go boom? I have and it's not pretty.
A cheaper "home style" battery charger won't bring back a totally dead battery sometimes. A good industrial or mechanics battery charger can bring back a totally dead one sometimes when a auto parts store compact charger won't.
I've had luck with hooking it up to my charger and setting it to 6 volts instead of 12 overnight and then in morning setting it to 12 and it will charge normal.
Re: ACTIVATING a dead battery ?
[Re: second 70]
#2959459 08/31/2112:45 PM08/31/2112:45 PM
a year or so ago, i got one of those pulse battery chargers that supposedly work on any type of battery. i had a sears AGM battery that only had a .07v reading, as it had sat for many years. i hooked up a regular lead acid battery with jumper cables [4ga] and let them hooked up for a couple days, then hooked up the pulse charger to both of them for quite a while. i let them both set for a couple of days, then hooked up the pulse charger again. after a while, both checked at 12.2v. i then charged the lead acid battery up. that didn't take long, then hooked the charger to the AGM battery. it was on for quite a while, but didn't get over 12.2v. i then let it sit for a couple of days, and it [the AGM battery] registered 10.3. after a couple of weeks, it checked at 9.7. the last time i checked it, it was 5.62. that was a few days ago. a guy could get it back to 12.2 easy enough [i think], but i'm guessing it wouldn't load test fer $hit. might be a good battery for testing circuits not requiring much load. this is just my trial and error experiment. i don't know if it relates in any way to the topic at hand, but i found it interesting i could charge an almost completely zero volt battery back to 12 volts, and after many months of sitting around, it still has 5.62 volts registering.
Re: ACTIVATING a dead battery ?
[Re: moparx]
#2959634 08/31/2106:36 PM08/31/2106:36 PM
Did it freeze? A dead battery will freeze and break connections between cells, toss it. Water in it? If just phosphated it can come back but takes a very long time.
Re: ACTIVATING a dead battery ?
[Re: TJP]
#2959636 08/31/2106:44 PM08/31/2106:44 PM
What kind of battery are we talking about here? A sealed maintenance free or one you can pull caps or an AGM? Makes a difference. Tread carefully when dealing with dead batts. They can be sulfated, they can be shorted and they can be full of gas. Ever seen a battery go boom? I have and it's not pretty.
And can make 130.00 or so seem cheap
Cheap? Well, you've certainly come to the right thread.
Earning every penny of that moderator paycheck.
DBAP
Re: ACTIVATING a dead battery ?
[Re: Dcuda69]
#2959645 08/31/2107:05 PM08/31/2107:05 PM
What kind of battery are we talking about here? A sealed maintenance free or one you can pull caps or an AGM? Makes a difference. Tread carefully when dealing with dead batts. They can be sulfated, they can be shorted and they can be full of gas. Ever seen a battery go boom? I have and it's not pretty.
Is this why I was taught at a very early age to pop the caps on a traditional lead acid battery when charging? Don't know that this would really prevent anything but my dad had me doing so early on to "let gasses escape"
Doc, a 3-4+yr old battery in our climate is basically used up anyway. If its an AGM unit and fully discharged, I have had good results with the description NITROUSN gave of adding 2nd at least currently charged battery, paralleled with the first. For some reason AGM batteries are very difficult to recharge when completely discharged. Used to work law enforcement fleet. People were always forgeting to turn stuff off. Had to find a remedy and the 2nd battery deal was the ticket. Lead acid batteries were easier to recharge after total discharge. Major battery reps all agreed. They all suggested a recharging rate of max 14.5volts on AGM batteries also.Don't use a marine style battery for your engine battery except in a pinch(temporarily). They weren't designed for continual high amp draw of you starting system.Its Florida and its warm. Most any fully charged 12volt battery will crank up an RV to get it moved(unless it's a big diesel). There are signs for $35 car batteries all over the main roads in Fla. Drop one in and get your vehicle moved. Cheapest way out. Good luck Bill
Re: ACTIVATING a dead battery ?
[Re: dOc !]
#2959666 08/31/2108:03 PM08/31/2108:03 PM
cB .... this is the battery out of the older Airstream motor home....,
Not been driven for FOUR YEARS ......
I tried that activate for 15 minutes ... zip ‘
It’s now been on at the shop for over an hour .... 100 amps !
I’ll report back .....
I don’t think a trickle charger would do a thing !
We could give Doc the basic information on how to use a battery hydrometer to check specific gravity of each battery cell so as to find the bad cell, replace the acid in that bad cell with distilled water, then charge that battery for many hours with a pulse type desulfating charger, OR We could give Doc the basic information on how to go about locating the lost Hydrogen Bomb in the South Carolina coast swamps, how to remove it from the mud, and how to bore a hole in the bomb casing, Question: which would result in less fatalities?
Curious Minds Want to Know....
Re: ACTIVATING a dead battery ?
[Re: 360view]
#2959865 09/01/2111:35 AM09/01/2111:35 AM